Nonlinear Fabry-Perot Cavity Research Articles

Positive pulse switching in coupled nonlinear Fabry-Perot cavities

It is shown that positive pulse switching is possible in a system of two coupled nonlinear Fabry-Perot cavities. The conditions in which a signal beam can be switched on and off by positive pulses in the steady state regime are described for cavities filled with Kerr media having a long diffusion length.

Dispersive optical bistability in a nonlinear interference filter using an intracavity nematic liquid crystal film with hybrid molecular alignment

Optical bistability in a nonlinear Fabry-Perot resonator due to reorientational effects in a thin intra-cavity nematic liquid crystal film with hybrid molecular alignment has been investigated. The influence of the initial resonator-detuning, which can be altered by temperature control, on the dynamics of the system and the dependence of the transmission characteristic of the nonlinear Fabry-Perot cavity on the cavity-finesse are shown. A refined theoretical way of describing liquid crystals in a Fabry-Perot resonator gives good agreement with experimental results.

Optical dispersive bistability in media with forced girotropy

In this paper the results of an analysis concerning the course of optical dispersive bistability in media with forced girotropy (the Faraday effect) are presented. It is shown that radiation transmitted through a non-linear Fabry-Perot cavity reveals, apart from bistability of the intensity, bistable states of polarization. The elliptically polarized transmission radiation changes bistably not only the value of proportion of the semiaxes of the polarization ellipse and the orientation angle of its major semi-axis, but also the direction of the rotation of its electric vector.

Ultrashort pulse reshaping with a nonlinear Fabry–Perot cavity matched to a train of short pulses

Reshaping of ultrashort pulses is predicted to occur when a pulse train from a mode-locked laser is incident upon a nonlinear Fabry–Perot cavity whose length is matched to the period of the pulse train. The temporal shape of the transmitted pulses depends on the relaxation time of the nonlinearity of the Kerr medium inserted into the Fabry– Perot cavity. When the pulse duration is shorter than the Kerr relaxation time, considerable pulse narrowing (by factors of 101–103) is predicted. If the Kerr relaxation time is longer than the period of the pulse train, the analysis shows the existence of two temporal shapes of the output pulse, leading to the possibility of bistability between these two states. A Kerr nonlinearity with an instantaneous response can be used to generate square output pulses. Both the transient and the permanent regimes are investigated, and analytical expressions for the narrowing factors are found.

Two-level description of instabilities in nonlinear Fabry–Perot cavities

The intracavity absorption (or gain) coefficient of two-level atoms embedded inside a Fabry–Perot cavity has been demonstrated to be well represented by an equivalent two-level system. The parameters of this new two-level system are simply related to that of the medium and to the cavity characteristics. When associated with well-known results of fluorescence spectra and nearly degenerate four-wave mixing in two-level media, this equivalence provides a universal description of intracavity resonance fluorescence and relaxation oscillations in any nonlinear absorptive, amplifying, or dispersive Fabry–Perot cavities.

Optical Bistability In Cylindrical Pixels

It is essential to pixellate arrays of optically bistable switching elements in order to remove cross-talk caused by diffusion. We solve for the problem of cylindrical pixel nonlinear Fabry-Perot cavities, illuminated by nonuniform radiation beams, accounting for carrier diffusion and surface recombination. It is found that the additional carrier sink produced by the transverse surface is not detrimental to the switching power if the pixel area is small enough or if the surface recombination velocity is low enough.

Polarization bistability in a nonlinear birefringent Fabry-Perot cavity

Polarization bistability and switching are described theoretically and demonstrated experimentally for a birefringent nonlinear Fabry-Perot cavity.

Single beam two-photon optical bistability in a submicron size Fabry-Perot cavity

We describe a semiclassical theoretical model on two-photon optical bistability in a nonlinear Fabry-Perot cavity filled with molecules having large permanent dipole moments under the plane wave and mean field approximations. The mathematical analysis follows with the assumption of a two-level system with large permanent dipoles. In the steady state situation, field equation is shown to provide the bistable behavior of the nonlinear cavity when resonant with two-photon excitation under certain conditions. It is shown that for a large difference in permanent dipole moment \mu_{0} = (\mu_{aa}-\mu_{bb})/2 between levels |a\rangle and |b\rangle, (\mu_{0}^{2}/|\mu_{ba}|^{2}\gg1 , where μ ba is the transition dipole moment), the two-photon optical bistability can result in a submicron size Fabry-Perot cavity.

Optical bistability in a phase-conjugate Fabry-Perot cavity

We consider optical bistability in a nonlinear Fabry-Perot cavity in which one of the mirrors is a phase-conjugate mirror. Dispersive effects are shown to be absent in such a system. Bistability can be achieved by changing the phase of the incident light beam.

Transient counter-beam propagation in a nonlinear Fabry-Perot cavity

By adapting Moretti's self-consistent numerical approach to integrating the Euler equation of compressible flow, a unified complete temporal and spatial description of superfluorescence and optical bi-stability was undertaken. (The simulation includes material initialization as well as refractive transverse and longitudinal field boundary conditions appropriate to the cylindrical laser cavity). The respecting of physical causality in Moretti's method was maintained; but by using an improved derivative estimator at both the predictor and corrector levels, the overall accuracy was improved. The physical model includes nonplanar two-way Maxwell-Bloch propagation with spontaneous sources. The problem of dynamic transverse effects as they relate to soliton collisions is addressed. The calculations are based upon an extension of Mattar's previous semi-classical model for diffraction and phase effects in self-induced transparency at thick optical absorptions. The computational algorithm relies on the use of characteristics, but is strictly a finite-difference scheme. This explicit scheme involves the simultaneous integration along the time coordinate for both forward and backward wave. However, directional derivatives must be considered to appropriately take into account the mutual influence of the two light beams without violating the laws of forbidden signals. Particular case is exercised to maintain at least a second-order accuracy using one-sided approximations to spatial derivatives. Each forward/backward field derivative will be related to its respective directional history. A numerical approach in which the discretization is not consistent with these physical facts will inevitably fail. Thus the numerical algorithm must discriminate between different domains of dependence of different physical parameters. The physical process can now be analyzed with a degree of realism not previously attainable. Significant agreement with experimental observations is reported from the planar or time-independent analysis counterpart confined to the central portion of the beam.